Lauren just sent me this:

Google’s got in on this too and it’s free (just in US at the moment though):We’ve just launched the beta version of the Display Ad Builder tool, which will allow you to create and customize image, animated, and Flash ads for the Google content network from within your client’s account. If you’ve ever struggled with design resources for creating display ads or needed to whip something up for a client at a moment’s notice, the Display Ad Builder may come in handy next time those situations arise.  Within the tool, you’ll find templates that range from highly customizable to more finished styles. You can edit these templates and supply your own copy, logos, and images to make the message your own. We’ll be adding more templates as we move out of the beta stage, so check back for additional options. 

For more details on the Display Ad Builder and how to use it, see our Display Ads 101 site or watch this video tutorial.